RSS Feed Issues

Ever since I hit the one year mark of blogging (1/28/15) my feed has stopped working. The actual feed updates at https://www.frugalhack.me/feed but when I try to look at my posts on Feedly, it does not show any posts from 1/28/15 onward. Also, I use an RSS-Driven campaign in Mailchimp and it has it is having the same issue. None of my posts from 1/28/15 and later have been sent out. I’m not sure what’s going on and I would love some help. My blog is https://www.frugalhack.me